<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>输入圆锥的底面半径和高，然后弹出它的体积</title>
</head>
<body>
    <script>
        var r = prompt("input r"), h = prompt("input h"), v = (r*r*Math.PI*h)/3
        alert('圆锥体的体积为'+ v)
    </script>
</body>
</html>